Purpose: To determine the associations between a priori and a posteriori derived dietary patterns and a general state of health, measured as the accumulation of deficits in a frailty index.
Methods: Cross-sectional and longitudinal analysis embedded in the population-based Rotterdam Study (n = 2632) aged 45 years. Diet was assessed at baseline (year 2006) using food frequency questionnaires. Dietary patterns were defined a priori using an existing index reflecting adherence to national dietary guidelines and a posteriori using principal component analysis. A frailty index was composed of 38 health deficits and measured at baseline and follow-up (4 years later). Linear regression analyses were performed using adherence to each of the dietary patterns as exposure and the frailty index as outcome (all in Z-scores).
Results: Adherence to the national dietary guidelines was associated with lower frailty at baseline (β -0.05, 95% CI -0.08, -0.02). Additionally, high adherence was associated with lower frailty scores over time (β -0.08, 95% CI -0.12, -0.04). The PCA revealed three dietary patterns that we named a "Traditional" pattern, high in legumes, eggs and savory snacks; a "Carnivore" pattern, high in meat and poultry; and a "Health Conscious" pattern, high in whole grain products, vegetables and fruit. In the cross-sectional analyses adherence to these patterns was not associated with frailty. However, adherence to the "Traditional" pattern was associated with less frailty over time (β -0.09, 95% CI -0.14, -0.05).
Conclusion: No associations were found for adherence to a "healthy" pattern or "Carnivore" pattern. However, Even in a population that is relatively young and healthy, adherence to dietary guidelines or adherence to the Traditional pattern could help to prevent, delay or reverse frailty levels.
Keywords: Diet quality; Dietary patterns; Elderly; Frailty; Frailty index.